Oliver precoat filter

The Oliver precoat filter is a modification of the regular Oliver filter. It consists of a horizontal cylindrical drum, the outside pf which is made up of separate segments or compartments. The entire outside of the cylinder is covered with a filtering medium such as fine mesh wire or cloth. Each segment is connected to a discharge line, under vacuum, by a special valve on the end of the drum in such a way that suction is maintained while the drum rotates. A deposit (or precoat) of diatomaceous earth or Ref. Nat. Oaso. Mfr., February, 1934, p. 54. 

Rotary-type enclosed continuous filters are used Almost exclusively in solvent dewaxing because the solvents are valuable and because they usually, form explosive mixtures with air. The principle of operation is the same as that outlined on page 321 with regard to the Oliver precoat filter. However, a precoat is not employed in wax filtering, and the rotating drum is enclosed in a shell so that pressure can be applied (Fig. 12-4). Some plants employ vacuum rather than pressure. The wax cake is sprayed or washed with solvent while it is still on the drum. Closed filtering systems are required because the solvents must be... 

Only one once-through process (Fig. 21-ld), the Suspensoid process, has been applied commercially. The catalyst (spent lubricating-oil clay) passes through the cracking furnace along with the oil and is removed from the fuel oil by an Oliver precoat filter. ... 

FIG. 18-126 Operating method of a vacuum precoat filter. (DotT-Oliver, Inc. )... 

Fig. 10-15. Arrangement of equipment for the Oliver precoat method of contact filtration. Oliver United Filters, Inc.)...

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